Projectile



Jan. 6, 1953 J. A. M NALLY 2,624,281

PROJECTILE Filed Sept. 10, 1947 2 SHEETSSHEET l gvwc/wlm JAMES A. MCNALLY Jan. 6, 1953 J. A. M NALLY 2,624,281

PROJECTILE Filed Sept. 10, 1947 2 $HEETSSHEET 2 JAMES A. MC NALLYPatented Jan. 6, 1953 UNIT-ED sures PATENT OFFICE amaze-1 PRQJECTILEEla'mes AfMcNaElly, United States Navy Application September 1o,1947,:SerialNo.773,283 :2 (Cl. 102-49) Granted'under rifle 35.13. IS.code @1952, see. 266) This invention relates to projectiles and moreparticularly to proieetiles including novel means for increasing therange and accuracy thereof,

Heretofore, projectiles or missiles, such as rifle shells, bombs,rockets and projectiles carrying scientific instruments for determiningphysical conditions at remote locations, have been accelerated from zerovelocity and projected to the desired target or location throughapplication of externally applied forces thereto, -or upon operation ofa self-contained power unit', such as a rocket mechanism. *-In allinstances the projectile is accelerated to a maximum velocity-determined"by the characteristics of the propulsion means, and therefore, therange, accuracy and penetration force of such projectiles arelimitedt'hereby.

It is therefore an object ofthe present invention to provide novel meansfor increasing range and accuracy of projectiles, missiles and the like.

Another object is to provide 'aprojecti-le enema ing novel propulsionmeans operaiile when (a predetermined velocity is imparted to theprojectile for further "accelerating 'the projectile to extremely highvelocities whereby an increase in rangeand accuracy thereof is obtained.

Another object is to provide in a projectile adapted to be acceleratedto an initial velocity upon application of an externally applied forcethereto, novel means operahlewhen the projectile attains said initialvelocity to "further ac'c'eberate the projectile.

Another object is to provide in a projectile or the type adapted tolee-accelerated to an initial velocity upon application of anexternally'applied force thereto, a hot motive fluid reaction meansoperable when the projectile "attains a predetermined velocity forfurther accelerating the projeotile to'apreviously unattainabiehi'ghvelocity.

Still another object of the present invention is; to; provide aprojectile "having self-contained motive means for accelerating theprojectile from zero'velocity to 'a predetermined velocity and hotmotive fluid reaction means ioriurtheraccelerating'the projectile afterthe self-contained motive means is dissipated.

Still another object is to provide novel means for improvingtheareodynamic characteristics or projectiles.

Other objects and features of thepresen't invention will appear morefully hereinafter upon consideration of the following detaileddescription in connection with the accompanying drawings which discloseseveral embodiments of the invention. It is to beexpresslyunderstoodhowever, that the drawings are designed for purposes-2' of illustration only :and are not to 'be-con'strued' as a definitionof the limits of the invention, reference for the latter purpose beinghad to the appended claims.

In the drawings, wherein similar reference haracters denote similarparts throughout the several views:

Fig. 1 is a diagrammaticshowing in section, oira projectile embodyingthe principles of "therpresent invention;

Fig. 2 is a profile View of the rear end of the proj ectileshown in Fig.'1;

Fig. 3 isa-pro'file view of the forward end of. the projectiledisclosedin Fig. 1-;

Fig. 4'is a diagrammatic illustration, insection, of :a projectileconstructed .in accordance with another embodiment 'of'thepresentinvention, and

5 is an illustration of a feature .of the-embodiment disclosed in Fig.4.

*With reference "more particularly to Fig. 1 of the drawings, "aprojectile of the type adapted'to be accelerated to an initial velocityupon application of an external 'forcetheret'o, is disclosed thereinconstructed in accordance with the principles of the present invention.The projectile includes a cylindrical casing "[10 of streamlined formfor motion'to the-left as viewed in thecdrawing. The diameter-of thecasing 1-0 is constant at'therear portion thereof'while the forwardpohtion possesses a. gradually decreasing diameter extending toward theforward end and terminating inn cylindrical opening I I. The rear end'of the casing do is terminated by a wall l2 having an opening F3therein for the purpose that will.

input of a high pressure or combustion ichamber' i=5, A high velocitydischarge nozzle 16 is provid'ed between the output of the chamber 15and the opening 1-3. The nozzle 4 6 extends, with.

gradually hicreasing diameter, from the output of the chamber 1 5, insymmetrical relation with the'longitudi nal' axisof the easing nan,tothe-openin'g" annular fuel reservoir 1 of. icyline dri'cal' orosssection, is positioned. within the easing' to, in symmetrical relationwith respect to the longitudinal axis thereof, and in :close prox imitywith the chamber '15. Fuel conduit 18 is connected fluid communicationwith the reservoir-"l l' at'a point on'the peripherythereof. The conduit1-8 is connected through electrically operated valve I9 to annular fuelmanifold 20 associated with the combustion chamber I5. A plurality offuel injection nozzles 2| are radially positioned in the wall of thechamber I to form communications between the manifold and the combustionchamber I5. The valve I9 is normally biased in a closed pOsition andmeans are provided to move the valve I9 to an open position to form afuel communication between the reservoir I1 and the chamber I5 when apredetermined pressure exists within the conduit I4. Such means includesa pressure responsive contr l device 22 mounted in the conduit I4. Thedevice 22 functions in response-to a predetermined pressure within theconduit I4 to apply, through conductor 22 a signal to energize the valveI9 in manner described heretofore. A suitable igniter means 23, whichmay take the form of a spark plug or a chemically treated metallic wirefor producing a glow discharge when fluid at high velocity passesthereover, is provided in the combustion chamber I5 to ignite thecombustive mixture therein.

When the projectile is accelerated to an initial velocity due to theapplication of an external force thereto, such as for example, theforces applied upon firing the projectile from a rifle, or the force ofgravity when the projectile is utilized as an aerial bomb, air at highvelocities is injected or rammed into the opening II, and, due to thegradually decreasing diameter of the conduit I4, the air is injectedinto the combustion chamber I5 at extremely high pressures. Due to thecentrifugal forces created by the rotating projectile, fuel within thereservoir I1 is forced against the outer peripheral wall thereof toapply fuel to the conduit I8. The reservoir I! may be pressurized inconventional manner to force the fuel through conduit I8 against valveI9. When the pressure within the conduit I4 attains a predeterminedvalue to operate the device 22, the valve I9 is moved to open positionthereby supplying fuel under pressure to the manifold and into thecombustion chamber I5 through injection nozzles 2I. The injected fuel ismixed with the compressed air to form a highly combustive mixture withinthe chamber I5 which is exploded by the igniting means 23, automaticallyor in response to operation of the device 22. When combustion occurs asource of hot motive fluid is generated in the chamber I5. The hotmotive fluid is exhausted at high velocities through discharge nozzle I6applying a force to the projectile to increase the forward motionthereof.

In order to impart further rotation to the projectile to therebyincrease the accuracy thereof, a plurality of reaction vanes 24 aremounted in the exhaust nozzle I6 extending inwardly toward thelongitudinal axis of the casing Ill. As shown more clearly in Fig. 2 ofthe drawing, the vanes 24 are angularly mounted with respect to thelongitudinal axis of the casing ID to provide reaction membersresponsive to the hot motive fluid passing thereover for impartingrotation to the projectile about the longitudinal axis thereof.

As previously mentioned, means are also provided by the presentinvention for improving the aerodynamic characteristics of projectilesto further increase the range and accuracy thereof. Such means functionsto discharge a high velocity hot motive fluid jet along the outersurface of the casing I0, throughout the entire diameter thereof, from apoint adjacent the opening II, rearwardly toward the wall I2. Thepresence of a high velocity fluid jet along the outer surface of thecasing I0 effectively energizes the boundary layer formed thereon, toreduce friction, to prevent separation and to increase the overallaerodynamic characteristics of the projectile. As shown in Figs. 1 and3, the foregoing means comprises a circumferential discharge nozzle 25located in the forward end of the casing I0, adjacent and rearwardly ofthe opening II. The nozzle 25 is positioned to discharge a high velocityfluid jet rearwardly along the outer surface of the casing I0 throughoutthe entire area thereof. The nozzle 25 extends inwardly toward thelongitudinal axis of the casing I0 and terminates in a circumferentialmanifold 26. A plurality of conduits 21 form a fluid communicationbetween the manifold 26 and the combustion chamber I5 in such a mannerto transfer a portion of the hot motive fluid generated in thecombustion chamber I5 to the manifold 26 for energizing the nozzle 25.In order to produce a high velocity fluid jet from the nozzle 25 thenumber of conduits 21, the dimensions of the nozzle 25, the manifold 26and the conduits 21 are properly proportioned to maintain the requiredpressure relationships.

In Fig. 4 of the drawings a projectile having primary propulsion means,such as a rocket motor for accelerating the projectile to an initialvelocity, is disclosed including novel features of the presentinvention. This embodiment includes certain features of the inventiondisclosed in Fig. l, and similar elements are designated bycorresponding reference numerals. The primary pro pulsion meanscomprises a rocket mechanism of conventional construction carried by acasing '39 including a plurality of rocket exhaust ports 3| in the rearend thereof. The casing 30 is designed for insertion in an exhaustnozzle 32 which also functions to form a discharge passage for the hotmotive fluid generated in the combustion chamber I5, in a manner similarto the exhaust nozzle I6 of Fig. 1. Upon ignition of the primarypropulsion means the projectile is accelerated thereby to a velocitydetermined by the characteristics thereof. As the energy of the primarypropulsion means dissipates the forces applied to the forward end of thecasing 30 by the pressures in the chamber I5 eject the casing 30 fromthe exhaust nozzle 32. After ejection of the casing 30, generated hotmotive fluid exhausts through the nozzle 32 applying forces to furtheraccelerate the projectile in a manner similar to operation of the Fig. 1system.

In this embodiment means are provided for supplying fluid under pressureto the combustion chamber I5 independently of axial rotation of thecasing II]. A resilient diaphragm 33, constructed of hydrocarbonresistant plastic material, is provided for separating the reservoir I?into a fuel chamber 34 and an air chamber 35. The fuel chamber 34communicates with the fuel conduit I8, while the air chamber 35 isinitially supplied with air under suitable pressure to maintain thesupplied fuel above a predetermined pressure throughout the period ofoperation.

Since the type of projectile disclosed in Fig. 4 is discharged from asmooth tube means are provided for imparting axial rotation thereto. Therocket mechanism exhaust ports 3| are angularly positioned with respectto the longitudinal axis of the projectile to impart rotation theretoduring operation of the primary propulsion means. As shown in Fig. 5,the means for imparting rotation to the projectile after the casing 36is discharged therefrom includes a plurality of reaction vanes 36pivotally mounted in slots 37 angularly positioned in the casing I0 withrespect to the longitudinal axis thereof. The vanes 36 are urgedinwardly toward the longitudinal axis of the projectile to extend withinthe nozzle 32 by the action of spring numbers 38. When the easing 30 isinserted into the exhaust conduit 32 the vanes 36 are forced intorespective slots 37. The flow of hot motive fluid through the nozzle 32reacts against the vanes 36 to impart rotation to the projectile in amanner similar to the arrangement shown in Fig. 1.

There is thus provided by the present invention novel means forincreasing the range and accuracy of projectiles. The novel means is socharacterized to be readily utilized in connection with rifle shells,rockets fired from smooth tubes and aerial bombs. Moreover, the novelmeans are constructed in such a manner as to operate automatically whenthe projectile attains a predetermined velocity to generate a source ofenergy for imparting further acceleration thereto. Furthermore, novelmeans are provided by the present invention for energizing the boundarylayer formed on the outer surface of the projectile to improve theaerodynamic characteristics thereof.

Although several embodiments of the present invention have beendisclosed and described herein it is to be expressly understood thatvarious changes and substitutions may be made therein without departingfrom the spirit of the invention as well understood by those skilled inthe art. For example, automatic pressure responsive valvular means maybe employed at the input and output ports of the combustion chamber toprovide intermittent operation if desired. Furthermore, it is to beexpressly understood that the unused volume within the casing ID isprovided for carrying elements commensurate with the desired use of theprojectile, such as explosive charges for example when the projectile isemployed as a destructive missile. Reference therefore will be had tothe appended claims for the definition of the limits of the invention.

The invention described herein may be manufactured and used by or forthe Government of the United States of .America for governmentalpurposes without the payment of any royalties thereon or therefor.

What is claimed is:

1. In a projectile adapted to be discharged from a smooth bore meansincluding a casing, means forming a longitudinal opening through saidcasing, said opening including an input portion extending from theforward end of said casing with gradually decreasing cross-sectionalarea, a high pressure area of reduced cross-sectional area communicatingwith said input portion and an exhaust portion extending with graduallyincreasing cross-sectional area from said high pressure area to the rearend of said projectile, conduit means leading from said high pressurearea, a nozzle exhausting at the forward outer surface of the projectileand connected to said conduit means to discharge a high velocity fiuidjet rearwardly along the outer surface of said casing throughout theentire area thereof, said exhaust portion including a plurality ofmovable reaction vanes pivotably mounted in slots annularly positionedin said casing with respect to the longitudinal axis thereof, saidreaction vanes imparting rotation to said projectile, propulsion meansmounted in said exhaust portion operable to accelerate said projectileto a certain velocity, means including an annular fuel reservoirsurrounding said high pressure area and a fuel conduit, means in saidfuel conduit to control the amount of fuel from said annular reservoirto said high pressure area for generating a source of hot motive fluidin said pressure area for discharge through said exhaust conduit tofurther accelerate said projectile after discharge of said propulsionmeans.

2. In a projectile adapted to be discharged from a smooth bore meansincluding a casing, means forming a longitudinal opening through saidcasing, said opening including an input portion extending from theforward end of said casing with gradually decreasing cross-sectionalarea, a high pressure area of reduced cross-sectional area communicatingwith said input portion and an exhaust portion extending with graduallyincreasing cross-sectional area from said high pressure area to the rearend of said projectile, conduit means leading from said high pressurearea, a nozzle exhausting at the forward outer surface of the projectileand connected to said conduit means to discharge a high velocity fluidjet rear- Wardly along the outer surface of said casing throughout theentire area thereof, said exhaust portion including a plurality ofmovable reaction vanes pivotably mounted in slots annularly positionedin said casing with respect to the longitudinal axis thereof, saidreaction vanes imparting rotation to said projectile, propulsion meansmounted in said exhaust portion operable to accelerate said projectileto a certain velocity, said propulsion means mounted for discharge fromsaid exhaust portion by the pressure in said pressure area afterdissipation of the energy thereof, means including an annular fuelreservoir surrounding said high pressure area and a fuel conduit, meansin said fuel conduit to control the amount of fuel from said annularreservoir to said high pressure area for generating a source of hotmotive fluid in said pressure area for discharge through said exhaustconduit to further accelerate said projectile after discharge of saidpropulsion means.

JAMES A. MCNALLY.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,376,316 Chilowsky Apr. 26, 19211,994,490 Skinner Mar. 19, 1935 2,246,429 Brandt June 17, 1941 2,410,538Walton Nov. 5, 1946 2,419,866 Wilson Apr. 29, 1947 FOREIGN PATENTSNumber Country Date 1,734 Great Britain 1876 14,000 Great Britain 1896126,325 Great Britain May 15, 1919 637,043 Germany Oct. 19, 1936 866,598France May 26, 1941

